In Bloody Shambles Vol 1 (C.Shores & B.Cull with Y.Izawa, 1992), one Ki-48 is mentioned as lost between 8-15 Dec 1941 during the Philippines campaign (p 186). No specific cause is attributed to the loss.

I wonder if-in the intervening 25 years-anyone has looked into the loss of this a/c (and would make their research known) ?

Doomed At The Start:American Pursuit Pilots in the Philippines, 1941-1942.
Bartsch,William H.
N.P.:Texas A & M University Press,1992.

I can't access my copy at the moment, but Chris Shores et al mention, in Vol.2 of Bloody Shambles (p.8):

After publication of Volume One, William Bartsch's excellent new book 'Doomed at the Start' (Texas A & M University Press) appeared, covering in great detail the activities and operations of the USAAF fighters in the Philippines. From this certain corrections are required to Chapter 5 of Volume One, as follows ... Shores goes on to list some of these corrections.

Can't recall in detail what Bartsch had to say, but it was comprehensive.

Better still, take a look at "December 8, 1941:Macarthur's Pearl Harbor", by the same author.